Not finding a solution, I decided to just uninstall/reinstall. Thankfully after patching to 1.05, it became playable and I was able to get passed the glitch and gradually move into the inner sanctum in the Vale.
I am currently sussing out the final battle with the King of Shadows, after dispatching Black Garius. After three attempts, I'vefailed each time at the mini-shadows, who don't seem to stop churning out of the statues. They eventually overwhelm my party, but I'm yet to try delaying Jerro's Web of Purity ability to get the most out of it. Next time...meanwhile, any other tips for the battle are welcome.